third_party/WebKit/Source/platform/geometry/FloatRoundedRect.h

/*
 * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
 *
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 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above
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 *    disclaimer.
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 *    copyright notice, this list of conditions and the following
 *    disclaimer in the documentation and/or other materials
 *    provided with the distribution.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
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#ifndef FloatRoundedRect_h
#define FloatRoundedRect_h

#include "platform/geometry/FloatRect.h"
#include "platform/geometry/FloatSize.h"
#include "third_party/skia/include/core/SkRRect.h"
#include "wtf/Allocator.h"
#include <iosfwd>

namespace blink {

class FloatQuad;

class PLATFORM_EXPORT FloatRoundedRect {
  DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();

 public:
  class PLATFORM_EXPORT Radii {
    DISALLOW_NEW();

   public:
    Radii() {}
    Radii(const FloatSize& topLeft,
          const FloatSize& topRight,
          const FloatSize& bottomLeft,
          const FloatSize& bottomRight)
        : m_topLeft(topLeft),
          m_topRight(topRight),
          m_bottomLeft(bottomLeft),
          m_bottomRight(bottomRight) {}

    Radii(const FloatRoundedRect::Radii& intRadii)
        : m_topLeft(intRadii.topLeft()),
          m_topRight(intRadii.topRight()),
          m_bottomLeft(intRadii.bottomLeft()),
          m_bottomRight(intRadii.bottomRight()) {}

    void setTopLeft(const FloatSize& size) { m_topLeft = size; }
    void setTopRight(const FloatSize& size) { m_topRight = size; }
    void setBottomLeft(const FloatSize& size) { m_bottomLeft = size; }
    void setBottomRight(const FloatSize& size) { m_bottomRight = size; }
    const FloatSize& topLeft() const { return m_topLeft; }
    const FloatSize& topRight() const { return m_topRight; }
    const FloatSize& bottomLeft() const { return m_bottomLeft; }
    const FloatSize& bottomRight() const { return m_bottomRight; }

    bool isZero() const;

    void scale(float factor);
    // Multiply all radii by |factor| and floor the result to the nearest
    // integer.
    void scaleAndFloor(float factor);

    void expand(float topWidth,
                float bottomWidth,
                float leftWidth,
                float rightWidth);
    void expand(float size) { expand(size, size, size, size); }

    void shrink(float topWidth,
                float bottomWidth,
                float leftWidth,
                float rightWidth);
    void shrink(float size) { shrink(size, size, size, size); }

    void includeLogicalEdges(const Radii& edges,
                             bool isHorizontal,
                             bool includeLogicalLeftEdge,
                             bool includeLogicalRightEdge);

    String toString() const;

   private:
    FloatSize m_topLeft;
    FloatSize m_topRight;
    FloatSize m_bottomLeft;
    FloatSize m_bottomRight;
  };

  FloatRoundedRect() {}
  explicit FloatRoundedRect(const FloatRect&, const Radii& = Radii());
  FloatRoundedRect(float x, float y, float width, float height);
  FloatRoundedRect(const FloatRect&,
                   const FloatSize& topLeft,
                   const FloatSize& topRight,
                   const FloatSize& bottomLeft,
                   const FloatSize& bottomRight);

  const FloatRect& rect() const { return m_rect; }
  const Radii& getRadii() const { return m_radii; }
  bool isRounded() const { return !m_radii.isZero(); }
  bool isEmpty() const { return m_rect.isEmpty(); }

  void setRect(const FloatRect& rect) { m_rect = rect; }
  void setRadii(const Radii& radii) { m_radii = radii; }

  void move(const FloatSize& size) { m_rect.move(size); }
  void inflateWithRadii(int size);
  void inflate(float size) { m_rect.inflate(size); }

  // expandRadii() does not have any effect on corner radii which have zero
  // width or height. This is because the process of expanding the radius of a
  // corner is not allowed to make sharp corners non-sharp. This applies when
  // "spreading" a shadow or a box shape.
  void expandRadii(float size) { m_radii.expand(size); }
  void shrinkRadii(float size) { m_radii.shrink(size); }

  // Returns a quickly computed rect enclosed by the rounded rect.
  FloatRect radiusCenterRect() const;

  FloatRect topLeftCorner() const {
    return FloatRect(m_rect.x(), m_rect.y(), m_radii.topLeft().width(),
                     m_radii.topLeft().height());
  }
  FloatRect topRightCorner() const {
    return FloatRect(m_rect.maxX() - m_radii.topRight().width(), m_rect.y(),
                     m_radii.topRight().width(), m_radii.topRight().height());
  }
  FloatRect bottomLeftCorner() const {
    return FloatRect(m_rect.x(), m_rect.maxY() - m_radii.bottomLeft().height(),
                     m_radii.bottomLeft().width(),
                     m_radii.bottomLeft().height());
  }
  FloatRect bottomRightCorner() const {
    return FloatRect(m_rect.maxX() - m_radii.bottomRight().width(),
                     m_rect.maxY() - m_radii.bottomRight().height(),
                     m_radii.bottomRight().width(),
                     m_radii.bottomRight().height());
  }

  bool xInterceptsAtY(float y,
                      float& minXIntercept,
                      float& maxXIntercept) const;

  void includeLogicalEdges(const Radii& edges,
                           bool isHorizontal,
                           bool includeLogicalLeftEdge,
                           bool includeLogicalRightEdge);

  // Tests whether the quad intersects any part of this rounded rectangle.
  // This only works for convex quads.
  bool intersectsQuad(const FloatQuad&) const;

  void adjustRadii();
  bool isRenderable() const;

  // Constrains the radii to be no more than the size of rect(); radii outside
  // of this range are not defined.  In addition, the radii of the corners are
  // floored to the nearest integer.
  // FIXME: the flooring should not be necessary. At the moment it causes
  // background bleed in some cases.
  // FIXME: this code is almost the same as adjustRadii()/isRenderable(). Get
  // rid of one of them.
  void constrainRadii();

  operator SkRRect() const;

  String toString() const;

 private:
  FloatRect m_rect;
  Radii m_radii;
};

inline FloatRoundedRect::operator SkRRect() const {
  SkRRect rrect;

  if (isRounded()) {
    SkVector radii[4];
    radii[SkRRect::kUpperLeft_Corner].set(topLeftCorner().width(),
                                          topLeftCorner().height());
    radii[SkRRect::kUpperRight_Corner].set(topRightCorner().width(),
                                           topRightCorner().height());
    radii[SkRRect::kLowerRight_Corner].set(bottomRightCorner().width(),
                                           bottomRightCorner().height());
    radii[SkRRect::kLowerLeft_Corner].set(bottomLeftCorner().width(),
                                          bottomLeftCorner().height());

    rrect.setRectRadii(rect(), radii);
  } else {
    rrect.setRect(rect());
  }

  return rrect;
}

inline bool operator==(const FloatRoundedRect::Radii& a,
                       const FloatRoundedRect::Radii& b) {
  return a.topLeft() == b.topLeft() && a.topRight() == b.topRight() &&
         a.bottomLeft() == b.bottomLeft() && a.bottomRight() == b.bottomRight();
}

inline bool operator!=(const FloatRoundedRect::Radii& a,
                       const FloatRoundedRect::Radii& b) {
  return !(a == b);
}

inline bool operator==(const FloatRoundedRect& a, const FloatRoundedRect& b) {
  return a.rect() == b.rect() && a.getRadii() == b.getRadii();
}

// Redeclared here to avoid ODR issues.
// See platform/testing/GeometryPrinters.h.
void PrintTo(const FloatRoundedRect&, std::ostream*);
void PrintTo(const FloatRoundedRect::Radii&, std::ostream*);

}  // namespace blink

#endif  // FloatRoundedRect_h